Conventionally, X-ray images acquired with a contrast material by X-ray diagnosis apparatuses are used for various types of manipulation. For example, X-ray images acquired with a contrast material are used for fluoroscopy roadmap that displays angiograms acquired with a contrast material in order to move a device, such as a catheter or a guide wire used for vascular treatment, forward to a site to be treated. Fluoroscopy roadmap has a fluoroscopy landmark function of acquiring an angiogram depicting the blood stream depending on injection of a contrast material into blood vessels and of displaying the acquired angiogram as superimposed onto a fluoroscopic image and a fluoroscopy subtraction function of canceling the background in order to allow easy observation of the blood vessels and the device.
It is preferable that an image of the blood vessels filled with the contrast material be used for angiograms used for fluoroscopy roadmap in order to allow clear observation of the blood vessels. In general, an operator checks images on a monitor and to use an optimum image. For example, when digital subtraction angiography (DSA) images that are captured in advance after a contrast material is injected into blood vessels are used, the operator selects an image of the blood vessels filled with the contrast material from among DSA image frames. For example, when an angiogram is created from a fluoroscopic image, the operator injects the contrast material during fluoroscopy and, while checking the fluoroscopic image, turns off the fluoroscopy when the blood vessels are filled with the contrast material and uses the last image hold (LID) at that time as an angiogram.